The world's first 100-megawatt compressed air energy storage project was completed in China-百兆瓦级空气储能
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The National Demonstration Project of 100 MW Advanced Compressed Air Energy Storage in Zhangjiakou City, Hebei Province is invested and constructed by Zhangb...

I added pure, because compressed air energy storage facilities already exist, that are larger, but rely on using natural gas and caverns.